Pile hammer having integral built-in surge tank and enclosed protected valve gear



April 22, 1958 J. J. KUPKA 2,831,461

FILE HAMMER HAVING INTEGRAL BUILT-IN SURGE TANK AND ENCLOSED PROTECTEDVALVE GEAR Filed April 10, 1957 2 Sheets-Sheet l INVENTOR. k/Z/m/J/fz/P/r/J April 22, 1958 J KQPKA 2,831,461

PILE HAMMER HAV IN TEGRAL BUILT-IN S GE TANK AND ENCLOSED PROTECTEDVALVE G Filed April 10, 1957 2 Sheets-Sheet 2 United States Patent JohnJ. Kupka, Gladstone, N. .L, assignor to McKiernan- Terry Corporation,Harrison, N. J., a corporation of New Jersey Application April 10, 1951,Serial No. 651,960

2 Claims. 01. 121-13 The invention here disclosed relates toreciprocating tools in the nature of power hammers particularly compoundhammers such as covered in copending patent application Serial No.550,718 filed December 2, 1955, now Patent 2,789,540 of April 23, 1957.

These hammers operate on steam or compressed air. To reduce and so faras possible eliminate fluctuations and otherwise improve the action, ithas been the practice to interpose a surge tank between the boiler orcompressor and the hammer. These surge tanks add objectionable bulk andconstitute somewhat of a hazard in that under the pounding, vibrationand rough usage of the hammer, they may disintegrate or break loose orotherwise create dangerous conditions.

One of the objects of the present invention is to utilize the desirablefeatures of the surge tank but to incorporate it in such a way as toavoid and eliminate objectionable features such as mentioned.

Another object of this invention is to free the hammer structure ofprojecting parts such as have heretofore been in the way, and in manycases, been broken loose or knocked off in the relatively rough handlingto which these machines are subjected.

Particularly, it is a purpose of this invention to protect the valvegear and to locate it where it cannot be broken off or injured even insuch rough action as skidding the hammer over the ground as sometimeshappens.

Other important objects of the invention are to prevent icing up of thevalve mechanism in the case of air operation, and to prevent excessivecondensation in the case of steam operation.

Further objects are to simplify, strengthen, and generally improve thehammer structure and operation.

All the foregoing and other desirable objects have been accomplished bynovel features of construction,

combinations and relations of parts, as hereinafter described andclaimed and illustrated by way of example in the accompanying drawings.In the drawings referred to, a present, practical commercial embodimentof the invention is illustrated, but it will become apparent thatstructure may be modified and changed all within the true intent andscope of the invention as hereinafter defined and claimed.

Fig. 1 of the drawings is a vertical, sectional view of one of thehammers showing the ram up off the anvil far enough on upstroke for thecam on the ram to permit closing of the admission valve or, ondownstroke, for

the cam about to open the admission valve to initiate the PatentedApr-.1212 l 2 operating in the lower cylinder, with'an intermediateannular shoulder 23 opposed to the intermediate head 17 and providingwith the surrounding upper cylinder wall, an annular expansion chamber24.

Steam or compressed air-is supplied at 25 to the lower end of the chest26 containing admission valve 27, the latter having a roller '28engageable by a cam 29 on the lower end of the upper piston portion ofthe ram. 9

In operation of this machine, the admission valve 27 closes as pistoncam 29 leaves engagement with roller 28 and expansion continues untilapproximately three-quarters upstroke, whereupon a differential valve 34operates to close 01f the exhaust valve and open a transfer orcompounding valve for passing partially expanded live steam or air frombelow to above the piston for cushioning upstroke and for acceleratingdownstroke of the piston.

When the admission valve is openedby engagement of cam 29 with valveroller 28 at the end of the downstroke of the ram, live steam orcompressed air will be passed from chest 26. up through passages 42 andout through ports 35 into the expansion chamber 24 beneath the upperpiston portion of the ram.

In the present invention, the steam chest 26 is extended upward to nearthe top of the hammer to form a surge tank or chamber 100 of substantialproportions, and a special feature of this construction is that theWalls forming this enclosure are integral with the upper cylinder andconstitute, in effect, integral reinforcements of the same.

A further important feature is that the dilferential valve 34 is locatedwithin this surge chamber, where it is guarded and protected againstmechanical injury and where it is preheated, lubricated, and kept insmooth working condition, and from which it directly derives thepressure for actuating it in'one direction.

5 This differential valve maybe considered as similar to that shown inFig. 5 of Patent 2,789,540 involving an upper smaller diameter piston 49and a connected lower larger diameter piston 50 carrying a cam 63 foractuating valve 68 controlling transfer of partially expanded steam orair from exhaust ports in the cylinder up through passage 60 and ports61 into the top of the cylinder above the piston.

These passages and ports 60 and 61 serve alternately for compounding todrive the piston downwardly and for exhausting from the top of thecylinder during upstroke of the piston as controlled by the differentialvalve.

This valve is operated automatically in the present invention by takingpressure from the expansion chamber 24 through a passage 57 to theunderside of the lower larger diiferential piston 50 and by leaving theupper smaller differential piston 49 exposed to the live steam orcompressed air pressure in the surge chamber by way of opening 33 in thetop of the upper differential cylinder 55.

With full pressure from the expansion chamber on the lower largerpiston, the two connected pistons will be raised to the upper positionto open exhaust ports and permit escape from the top of the cylinderdown through passage 60 and out the exhaust pipes 58 and, as pressurereduces as the ram piston approaches the top of its stroke, the normalpressure present in the surge chamber acting on the upper smaller pistonthrough opening 33, will force the differential pistons downward toclose the exhaust valve and open the compounding valve 68 to transferthe partially reduced pressure power forces up through passage 60 intothe top of the cylinder for cushioning upstroke and acceleratingdownstroke of the ram.

The dilferential valve is shown solidly secured to the body of thecylinder by bolts 92, and the admission valve by bolts so that thesevalves may be readily removed and replaced as separate, independentunits, after removal of the cover plate 102 closing the surge chamber.

This cover is shown as of relatively large size so as to provide fullaccess to the interior of the surge chamber and as recessed within asurrounding flange 103 so as to be protected against abrasion and otherforces such as might result from skidding or sledding the hammer on itsside.

The surge chamber cover is shown removably secured by stud bolts 104 anda supplemental cover 86 is shown secured by bolts 88 on the main cover,providing access to the admission valve without requiring removal of thelarge main cover.

be, the hammer may be dragged or pushed over ground or other supportingsurface without injury.

The location of all valve mechanism within the surge chamber attordsmechanical protection of such parts and desirable preheating andanti-icing characteristics. By admission of steam or compressed air, thevalve mechanism will be preheated, ready to start operations even afterlong shut-down under exposed cold weather conditions. This preheatingand maintaining the valve gear in heated condition, reduces condensationand, in the case of compressed air operation, prevents icing up.

The location of the valve gear in the surge chamber also avoids need forseparate connections to operate the ditferential valve since this valvecan then take the normal pressure for balancing it against the variablepressure directly from within the surge chamber by a simple open passage33.

The construction is simple and rugged and all moving parts are fullyprotected withinan enclosure which in addition to serving as a surgechamber, reinforces the construction and effects preheating and deicingand facilitates lubrication since lubrication of these machines isusually elfected by introducing lubricant with the steam or air and thisadmitted to the surge chamber in heated condition operates to thoroughlylubricate all parts.

The integral surge chamber encloses all cylinder passages and ports,reducing heat losses and aiding preheating.-

The upper and lower ends of this chest are shown as rounded to ride overa supporting surface and reduce obstruction in the case of it beingnecessary to drag the hammer as in shifting from one location toanother.

What is claimed is:

1. Power hammer comprising the combination of cylinder and ramreciprocating therein, said cylinder having a longitudinally extendingintegral surge chamber on one side thereof provided with an inlet foractuating fluid at the lower end, an admission valve in the lowerportion of said chamber controlling communication between the interiorof said chamber and the cylinder, and valve mechanism in the upperportion of said surge chamber controlling communication between oppositeend portions of the cylinder and including passages communicating withthe cylinder enclosed within said surge chamber.

2. Power hammer comprising the combination of cylinder and ramreciprocating therein, said cylinder having an integral surge chamber onone side and dilferential valve mechanism enclosed Within said surgechamber and connected to control passage of motive fluid to and from thecylinder, said differential valve mechanism including opposed pistons ofdifierent areas and a connection extending from the cylinder to one. ofsaid pistons, and a connection to the other of said pistons open to theinterior of said surge chamber.

References Cited in the file of this patent UNITED STATES PATENTS

